In her story Mr. Rabbit is concerned about his new neighbors, the Otter Family, who recently moved into town and he just doesn't know ANYTHING about these strange animals. Mr. Owl advises him to just "Do unto otters as you would have otters do unto you". This includes the saying please and thank you, sharing, being honest and "co-otter-ating". This book would be a great addition to child's Easter basket. (And there are a fair share of adults who need a reminder about the golden rule too!).
And here is Keller's list of "office otter-quette":